RLyon
Harmless
Posts: 9
Registered: 7-5-2025
Member Is Offline
Mood: No Mood
|
|
Sheradization of Copper.
Wondering if I can get some help here- I do alot of copper electroforming and I'm interested in plating a layer of zinc, heating- and producing a
brass (ish) finish on my work. I've done this successfully with a zinc electroplate but it seems sort of extra work when you can easily coat the
surface with zinc dust and a simple water based binder.
HOWEVER - this doesn't work at all in the kiln- none of the zinc diffuses into the copper, it all flakes off.
Any suggestions?
|
|
|
Sulaiman
International Hazard
Posts: 3947
Registered: 8-2-2015
Member Is Offline
|
|
just guessing ....
maybe you could dip the copper in molten zinc
then put it in the furnace.
I GUESS that the zinc coating will melt (>420oC)
then some will diffuse into the copper
and a lot will boil off (> 907oC) and oxidise
If too much zinc is diffused in, maybe re-heating would evaporate away some of the zinc?
zinc fumes should not be inhaled.
IF you try, (with a 'disposable' test piece) please report your results - just my curiosity
PS Sheradization iusually means zinc on iron/steel.
[Edited on 14-12-2025 by Sulaiman]
CAUTION : Hobby Chemist, not Professional or even Amateur
|
|
|
bnull
National Hazard
Posts: 995
Registered: 15-1-2024
Location: East Woods
Member Is Offline
Mood: Fecking annoyed
|
|
Quote: Originally posted by RLyon  | (...) coat the surface with zinc dust and a simple water based binder.
HOWEVER - this doesn't work at all in the kiln- none of the zinc diffuses into the copper, it all flakes off.
Any suggestions? |
Zinc must be in direct contact with copper for diffusion to happen. The binder merely coats the zinc particles and glues them to the copper surface.
It is a barrier between zinc and copper which the former can't cross. The "extra work" you want to avoid is what makes the "brassification" effective.
|
|
|
Fulmen
International Hazard
Posts: 1796
Registered: 24-9-2005
Member Is Offline
Mood: Bored
|
|
I think bnull is spot on. You need metal on metal contact, so no binder is likely to work. The only alternative I can think of is
something like vacuum deposition which is far more work than plating.
We're not banging rocks together here. We know how to put a man back together.
|
|
|
RLyon
Harmless
Posts: 9
Registered: 7-5-2025
Member Is Offline
Mood: No Mood
|
|
Got it thanks!- I figured with the water binder - it would evaporate at high temperatures just leaving the zinc on the surface of the copper.- but
maybe at the microscopic level this isn't enough contact. The works are sort of large- so ill probably need to brush plate the zinc. Ill post
something if I get anywhere. Im finding that the copper deforms pretty quickly under anneal temperatures- so Im not sure if I can get the zinc to
brassify without too much distortion. Ill shoot for lower temperatures and longer times and let you know..
|
|
|
RLyon
Harmless
Posts: 9
Registered: 7-5-2025
Member Is Offline
Mood: No Mood
|
|
PS Sheradization iusually means zinc on iron/steel.
[Edited on 14-12-2025 by Sulaiman][/rquote]
Btw- to this note- Sherard who developed the process also did several experiments on copper with zinc though its obviously less popular or well known-
unless of course you are doing the whole turn a penny gold experiment in class somewhere - in which case I dont think he gets credit 
|
|
|
bnull
National Hazard
Posts: 995
Registered: 15-1-2024
Location: East Woods
Member Is Offline
Mood: Fecking annoyed
|
|
| Quote: | | I figured with the water binder - it would evaporate at high temperatures just leaving the zinc on the surface of the copper. |
But then the surface of the zinc grains is oxidized and direct contact between the metals is prevented.
There is an article in the Journal of Chemical Education (I like this journal, full of fun stuff) called The "Golden Penny" Demonstration, by
Szczepankiewicz, Bieron and Kozik. It may give you some ideas.
[Edited on 17-12-2025 by bnull]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
